This invention relates to a tape-operating apparatus for recording and reproduction of sounds which is adapted for use with an endless loop type cartridge or a coplanar type cassette. Ordinary compact magnetic tape holders are broadly divided into an endless loop type cartridge and coplanar type cassette. Both types of tape holder have different characteristics and shapes, requiring separate sound recording and reproducing devices for the cartridge and cassette, as has been the case in the past. If a single tape-operating apparatus could be developed which is adapted for use with both types of tape holder, then recording and reproduction of sound using a magnetic tape would be carried out very conveniently. Under the present circumstances, however, where an attempt is made to incorporate two forms of sound recording and reproducing function in a single device, then said device would be rendered bulky and complicated in mechanical setup, giving rise to difficulties in operation.